Wind turbine



FIG. 1 is a front elevation view of a wind turbine showing my new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a top perspective view thereof;

FIG. 4 is another bottom perspective view thereof;

FIG. 5 is another top perspective view thereof; and,

FIG. 6 is a top plan view thereof. 

The ornamental design for wind turbine, as shown and described. 